


Biology Lessons

by vienn_peridot



Series: Citrus Basket [6]
Category: The Transformers (IDW Generation One), Transformers - All Media Types
Genre: AU: Merformers, Alien Culture, Alien Sex, Culture Shock, Dodgy Marine Biology, Hand Jobs, I'm Going to Hell, Mating Cycles/In Heat, Mer!Drift, Mer!Wing, Octo!Ratchet, Other, Plot What Plot/Porn Without Plot, Polyamory, Post-Coital Cuddling, Sticky Sexual Interfacing, Threesome
Language: English
Status: Completed
Published: 2015-04-16
Updated: 2015-04-16
Packaged: 2018-03-23 04:40:42
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 7,215
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3754909
Author URL: https://archiveofourown.org/users/vienn_peridot/pseuds/vienn_peridot
Summary: <blockquote class="userstuff">
              <p>Someone who was human up until a year ago STILL hasn't gotten the Mer version of the birds-and-bees talk. When his new body starts to act weird he has no idea what to do.<br/>Lucky for him he's got two friends who are more than willing to give him a practical demonstration.</p><p>This is the result of a dare to write OT3 merformer heatfic with tentacles -.-;</p>
            </blockquote>





	Biology Lessons

**Author's Note:**

> This is yet ANOTHER Mer AU where a human!Drift meets mer!Wing and octomer!Ratchet and somehow (MAGIC!) ends up becoming a mer himself, joining Wing and Ratchet's pod.  
>  **NOT** RELATED TO ASCW

Ratchet was half-heartedly stalking a large paddlecrab around an underwater rock formation when a voice came from somewhere above and behind him.

“Ratchet? Can I ask you something?”

The question was asked in a mangled combination of the local Mer dialect and surface-dweller English, but the healer understood anyway.

Only one member of their pod spoke like that.

“You get one more free question today then I start charging.” Ratchet replied as changes to the water currents moving over his tentacles told him Drift was moving overhead.

“I figured you’d say something like that,” Drift flattened his still-new fins in a motion that meant the same as a sigh and dropped a neat kelp-wrapped bundle of mussels infront of the red-and-white octomer.

“That was a joke, you know.” Ratchet said, carefully picking up the package. “I _do_ appreciate these kid; but you don’t have to take my grumbling seriously.”

Drift was speaking when he entered Ratchet’s line of sight, but no matter how hard he tried the octomer honestly couldn’t keep his mind on the once-human’s words. The younger mer’s hide almost seemed to glow from within, the white areas reflecting far more light than should be available at this depth. The bioluminescent red portions of his skin were far brighter than normal, almost begging to be touched.

Ratchet drew himself up unconsciously; he sunk his claws into the package of mussels and held it tightly to his chest as his fins flares wide, the motion carrying down through his body to end in a sensual undulation of his tentacles.

“See! That’s exactly what I mean!” Drift cried in frustration, throwing his arms up in a human gesture of frustration that was accompanied by jerky flares of his fins. “Everyone’s been acting really pissed off when they see me lately but nobody will tell me what the fuck I’ve done wrong! Wing’s acting like a total freak too so I thought you might want to tell me but _no!_ Just the silent treatment and that pissed-off shudder thing.”

Drift imitated Ratchet’s action angrily, exaggerating it so much the octomech was intensely grateful there was nobody else from the pod around to read his arousal in the shifting of his chromatophores.

Inhaling deeply through his gillslits, Ratchet took the plunge.

“Drift, nobody’s angry with you.”

“ _Really?_ Then why are they acting like they are?” Drift crossed his arms defensively; head cocked and fins at half-mast.

“They’re not,” Ratchet couldn’t quite meet Drift’s angry blue eyes as he forced the next words out. “They’re…flirting. You, uh… Your new body is preparing for its first breeding cycle and they are expressing interest. When you don’t acknowledge or return their gesture they assume you are already taken or not ready to select a partner yet.”

“So they’re not pissed?” Drift looked relieved for all of half a minute before the rest of Ratchet’s words sunk in. “Wait, breeding cycle? Everyone’s been flirting with me? And Wing- And I gave you mussels because I thought you were pissed and _you_ just did the thing… Oh shit.”

Drift buried his face in his hands, fins sinking to sit at a humiliated angle.

“I know how little you know of our ways, Drift. This is my fault for not explaining our biology to you sooner.” Ratchet shifted uncomfortably, coiling and uncoiling his tentacles around the rocky outcrop. “I honestly thought you would have more time to adjust before your cycles began.”

Something like a hysterical laugh interspersed with the sounds of an upset smolt came from Drift. He shook his head, dropping his hands from his face. He wore a strange, twisted smile that looked absolutely horrific with sharp Mer teeth behind it.

“Probably Wing and all those fucking _sharks_.” Drift said, looking wildly around before pinning Ratchet with a desperate look. “So what the fuck is going to happen now? I’m not ready to have kids!”

Taking a risk, Ratchet shifted his gift of mussels to one hand and held out an arm to Drift. Octomer were tactile in general, but Drift was leery of even casual contact while he adjusted to his new form.

With a ‘screw it’ expression on his face, Drift crossed the distance between them and slid in under the offered arm. He pressed himself wordlessly against the octomer’s side, seeking some sort of solidity in a world that had gone completely tits-up for the second time in less than a year.

Ratchet tried to restrain his instinct to enfold the younger Mer in all ten of his limbs. If he did that Drift would panic and maul him before he realised he wasn’t in danger.

“So what’s going to happen?” Drift asked, wrapping his arms around his own torso.

“Your colours brighten first, then your bioluminescent areas; a few days after that your genital area will become more sensitive than normal and start to swell a little. That’s the signal that you and whoever you’ve chosen should go find someplace to be alone for a bit.” Ratchet explained, trying to ignore the warm, powerful body pressed against his side. “The length of time varies from mer to mer. Our fertility rate isn’t terribly high, so even with a breeding cycle you aren’t certain to spawn.”

That seemed to reassure Drift. He relaxed against Ratchet’s side and even laid a hand on the place where one large tentacle emerged from base of the octomer’s torso.

“So what do I do if nobody wants to shack up with the freak?” He sounded calm, but the violent twitches of his fins and tail gave him away.

Ratchet couldn’t understand what Drift was getting at until he forcibly reminded himself that the land-walkers were very different from Mer-kind.

“Someone in the pod always helps. It is how things are done. If one suffers, all suffer and the pod is weakened.” The octomer wasn’t sure if his words made it through, so he added, “Don’t underestimate the power of attraction that something new holds, kid. You’ll be fine.”

“So what do I do? And what about Wing?” Drift asked.

Ratchet made a humming noise deep in his chest as he thought, feeling Drift begin to gently trace some of the more stable colour patches on his tentacles with a claw.

Without more knowledge of how the land-walkers interacted Ratchet couldn’t interpret what Drift intended. The touches could mean anything from the simple curiosity of a new fry to the blatant come-on of an adult. The octomer’s body knew _exactly_ what it felt in reaction to that light touch, making Ratchet extremely glad that Drift couldn’t properly interpret his colour-cues yet.

“Wing is worried that you don’t want him anymore.” A subdued voice said as Wing came slowly into view, fins flattened with shame. “You’re doing so well that I keep forgetting that there are a lot of things you still don’t know. I’m sorry Drift.”

Drift flared his fins in startled reaction to Wing’s sudden appearance appeared, moving instinctively to place himself between the intruder and the more vulnerable octomer before he realised who it was. When he saw who it was Drift’s fins fluttered with embarrassment and he let Ratchet shift him back to his original position against the octomer’s side. Wing glided closer to the pair but stayed just out of reach, fins still plastered to his body.

“’s ok Wing. I should have asked sooner instead of leaving it so long.” Drift gave a human shrug along with the up-down flick of fins the mer used. “I… I kinda reached the ‘be alone with a friend’ stage the other day and it’s been driving me fucking crazy because I had no idea what was going on and everyone seemed so angry at me and I figured it was because I was …you know… and you guys could tell and thought I was a perve or something.”

“You _what?!_ ” Ratchet demanded sharply, red and white rippling in sharp waves down his lower body “Why didn’t you say something?”

“I just did, didn’t I?” Drift said defensively.

“Ratchet, calm.” Wing said, moving to cuddle up to the other side of the octomer. “It is in the past and cannot be changed. What matters now is how we choose to move forward from here.”

Drift actually shrank in on himself at those words, unable to help the reflex action.

“Drift?” Wing peered over the bulk of Ratchet’s torso, face full of concern.

“Kid, you know I only bite if you wake me up too early.” Ratchet brushed a comforting tentacle over Drift’s arm. “What is it?”

Drift mumbled something in his English that neither mer could make out, the sounds not suited for their environment.

Eventually Drift tried again.

“I don’t want to have to choose.”

“What do you mean, choose?” Wing looked completely baffled as he reached out to gently stroke Drift’s crest.

“I don’t want to have to pick one of you, because I want you both.” Drift snarled, twisting to glare defiantly at both of them.

Wing and Ratchet looked completely bewildered, answering simultaneously.

“ _Choose?!_ ” “But you _can_ have us both!”

“WHAT?”

“During your breeding cycle you can mate with _any_ unattached mer that reciprocates your advances, kid.” Ratchet said, trying to force his gills to keep working.

“I can? So… you guys will help me?” Drift turned pleading blue eyes on Ratchet and Wing. “It actually kind of fucking hurts, see?”

To the shock of both Wing and Ratchet, Drift twisted to present his tail to them, spreading his pelvic fins with his hands in an incredibly vulgar way to display his swollen genital slit.

The twin heads of Drift’s depositors could be seen easily; they were peeking from the upper portion of Drift’s genital slit and had probably been semi-erect for the last several days. His cloaca was puffy and far more distinct than it would have been earlier in his cycle.

Everything about Drift practically screamed ‘fuck me’ to the two stunned mer.

Wing didn’t even bother to hide how much the unwittingly obscene display turned him on, even if the finer points of his body language went right over Drift’s head. Ratchet almost choked on empty water, his chromatophores making it absolutely clear what the sight of Drift baring himself did to the octomer.

Drift may have missed the general social cues, but he could hardly miss the one red area on Ratchet’s lower body that was highlighted by a wide swathe of white on before barber-pole stripes flowed down the tentacles.

“ _Woah_ , did I seriously just give you a boner?”

“Yes, you horror.” Ratchet growled, twitching aggressively.

Wing laughed, slipping a hand between Ratchet’s tentacles to lightly caress the engorged hectocotylus that had descended from its hiding place within Ratchet’s body. He purred as two of Ratchet’s tentacles responded by winding around his arm, gently caressing the webbing between his fingers before moving up to the mer’s forearm fins.

“You did. And it’s a very nice one, too.” Wing said, slowly running the pads of his fingers over Ratchet’s erection.

“Fuck, this is just like that hentai.” Drift said with eyes wide and fixed on the pair blatantly groping each other. “I know what’s coming next.”

“And what’s that, Mr Know-It-All?” Ratchet asked sharply, slowly trailing one of his lower limbs down to slide against Wing’s genital slit.

“Tentacles. Holes. Fucking.” Drift stated, looking smug.

“ _Wro-ong!_ ” Wing practically sang, twisting and moving up onto the octomer’s lap to give Ratchet better access to his genital slit. His hand never stopped moving on Ratchet’s hectocotylus, making interesting patterns flash across the tentacles roving across his body.

“Oh yeah, so what do you think’s gonna happen?” Drift demanded, challenging the mer’s authority.

The recently-made mer was obviously losing the battle against his breeding cycle and the provocation of watching Wing and Ratchet molest each other right in front of him. His depositors were slowly sliding out from between his pelvic fins, which were twitching slightly as the internal muscles of his cloaca tightened in search of stimulation.

“We’re going to tease you until you forget those silly human hang-ups and let us show you how it’s done down here.” Ratchet’s voice held a low throbbing note that vibrated right through both of the finned mers.

“I’d like to see you try.” Drift said, visibly relaxing.

Wing and Ratchet traded amused looks, each making a move as they thought the other distracted.

Wing grasped Ratchet’s hectocotylus and lightly stroked it from base to tip at the same time Ratchet used two tentacles to spread Wing’s pelvic fins in the same lewd gesture Drift had just unwittingly used. The bold touch made Ratchet press a little harder than he intended as pleasant sensations rippled through him. Wing gasped and arched under the pressure, presenting his genital slit to Drift as his fins flared. The mer’s hand slipped along Ratchet’s tentacles and lost track of its target.

“Responsive, isn’t he?” The octomer asked rhetorically, “Remember who you’re talking about here, Drift. This is _Wing_. He has a bad habit of achieving practically _anything_ he sets his mind to.”

“He’s right about that.” Wing said smugly, wriggling himself into a more comfortable position in Ratchet’s hold. “I’m _definitely_ going to enjoy proving you wrong today. _And_ watching Ratchet prove you wrong, and then proving you wrong _right along with him_.”

Wing purred the last words as one wandering hand found Ratchet’s cloaca, hidden in the complex folds at the base of his tentacles. He continued to search for the distinctive texture of the octomer’s hectocotylus with the other hand.

Laughing yellow eyes watched hungrily for Drift’s reaction as Wing gently stroked the back of his knuckles over Ratchet’s opening. The octomer’s grip on Wing firmed in retaliation and red and white chased themselves over his lower body in an unmistakable pattern of arousal.

Drift wasn’t unaffected by the show. Wing could see the other mer’s depositors as they continued to extend and forced his pelvic fins aside.

“Careful down there small fry, or I’ll wear you out before Drift decides to join in.” Ratchet growled, sliding his hands over Wing’s headfins and rolling the tips of two tentacles along the full length of the trapped mer’s genital slit. “You know you don’t have the stamina to match me yet.”

Wing moaned and twitched, trying to direct the pressure to where he wanted it. Ratchet simply moved with him, grinning as Wing’s depositors began to make an appearance. Their audience of one moved closer, curiosity and the unrelieved arousal of his breeding cycle getting the better of him.

Not as distracted by the hand near his cloaca as Wing would like him to be, Ratchet noticed Drift’s movement and mer’s fascination with the suggestive fluttering of Wing’s fins.

“Would you like to touch?” Ratchet offered, spreading Wing’s pelvic fins a little wider.

“Mmmmm, _please_ do.” Wing said, flaring in a beautiful display. “Otherwise this ten-limbed tease will just keep playing until I implode.”

Drift’s eyes were wide, dazedly following the tempting little dance two red-and-white tentacles were doing around Wing’s cloaca and depositors. His mouth was slightly open and he licked his lips in a very human gesture came across as predatory.

“Have you guys… You know, um.” Drift trailed off, mouth opening and closing on silence as Ratchet flicked lightly across Wing’s fully extended depositors.

“Have we… _aaaaaaaaahhhh_ … done this before?” Wing asked when he finished moaning.

Drift nodded violently, unable to tear his eyes away from what the octomer was doing.

“Many times.” Wing said happily, finally relocating Ratchet’s hectocotylus and wrapping his fingers lightly around it.

“Wing here has a thing for tentacles.” Ratchet explained, voice hitching as Wing began to slowly stroke both his hectocotylus and cloaca with alternating motions.

“Weird.” Drift’s tone was full of scorn but his body language screamed the opposite as he edged closer.

“But you like me anyway.” Wing was smug, fins rippling as he adjusted his position.

“Yeah.” Drift sighed, resigning himself to the fact that his soon-to-be mates really were going to carry through on their promise of teasing him half to death.

The once-human watched intently as the two mer continued to fondle each other, Wing clicking happily and arching into the light touches of what was now five tentacles against his depositors and cloaca as Ratchet held him close. Drift couldn’t see what the finned mer was doing since his arms were only visible from the elbow up, but Wing giving just as good as he got if the reactions he got from Ratchet were making were anything to go by.

Deep infrasonic groans and sharp colour changes accompanied every little shift of Wing’s upper arms and the tentacles holding him started to twitch uncontrollably. Wing smirked fit to split his face when Ratchet grabbed his arms and forcibly stilled them. The octomer’s eyes were closed and his face screwed up in a look of intense concentration.

“Looks like _someone_ was a little more worked up than I thought.” Wing sounded incredibly smug.

“Shut up.” Ratchet growled, pinching the tips of Wing’s depositors to make the mer gasp.

“So how does it work, anyway.” Drift asked, shifting uncomfortably as his depositors throbbed. “I mean, I get how the, um, _passage_ can be multi-purpose, but two dicks? Isn’t that a bit of overkill or something?”

Wing laughed breathlessly and bucked in Ratchet’s hold, fins quivering at full extension as Ratchet stroked the parts Drift had mentioned on the tentacle-bound mer with a delicate touch. The octomer chuckled low in his torso when Drift’s hands made an abortive twitch in the direction of his own equipment.

Ratchet slipped a hand over Wing’s lower face and slid two fingers into his mouth, keeping the notoriously mischievous mer from teasing Drift about his understandable lack of knowledge regarding mer anatomy.

He almost regretted doing so when Wing scraped his teeth ever so gently over the knuckles of the invading digits and slid his tongue expertly against the webbing between them.

“It’s _hardly_ overkill. They both serve a purpose as they form an integrated system.” Ratchet explained, continuing to fondle Wing’s genital slit. “It would be easier for you to understand if we show you while I explain. If Wing here is willing to help demonstrate…”

Wing nodded violently, squirming and thrusting himself up against Ratchet’s busy tentacles.

“Excellent.” Ratchet said, using two tentacles to completely enclose one of Wing’s depositors.

The captive mer writhed and bucked into the contact, his gills flaring in a gasp.

“As you see, only one depositor is inserted into the cloaca during any given mating session.” Ratchet began, rippling the tentacles around his chosen depositor. “Once inside, it will expand so that it doesn’t slip out during copulation.”

As if on cue, the tip of Wing’s depositor peeking out from the end coil of the pair of tentacles expanded, spreading to fit the space Ratchet had given it. Drift moaned, clenching and unclenching his hands in time with the unconscious flaring of his fins.

“This action also has the happy side effect of keeping any milt escaping from the receiving mer before it reaches the internal brooding chamber.” Ratchet continued milking Wing’s depositor with his tentacles throughout his explanation.

By now Wing was thrashing, only the firm grip of Ratchet’s arms and tentacles keeping him from smashing into the rocky outcrop and injuring himself.

Drift wasn’t sure where to look.

Wing’s face was a mask of pure desire, from half-closed eyes that hadn’t left Drift to the tongue flicking out from time to time around the two fingers that did very little to stifle his moans, clicks and chirrups of pleasure.

But the subject of their lesson was lower down, where two tentacles spread the mer’s pelvic fins wide in what Drift was slowly coming to understand as a lewd display. One tentacle slowly caressed Wing’s cloaca, rubbing the now slightly swollen opening. The other two pumped away at his depositor, keeping a firm grip on the shaft as Ratchet continued the massage Wing was quite obviously enjoying.

“This is where the other depositor comes into play.” Ratchet’s voice dropped and became huskier than Drift had ever heard as he continued his lesson. “The depositor left outside the body takes in seawater. At the moment of orgasm it will use this seawater to aid the flow of milt into the accepting mer’s cloacal passage.”

Wing was quite obviously approaching said orgasm. His movements became sharper and more desperate as he neared release.

“ _Some_ have developed the ability to take in so much water through the external depositor that their mate is injected with a large amount of very dilute milt, producing a full feeling.” Ratchet continued, “And some have perfected this skill to the point where their mates will even be able to feel the fullness of their brooding chamber if they press on their abdomen a little after mating. Wing really enjoys that full feeling, which is part of his _fascination_ with octomer.”

Ratchet dropped his voice right into a low register that seemed vibrate right through Drift’s entire body and Wing came undone, keening on a high note. He arched strongly against Ratchet’s hold as both of his depositors pulsed. Visible ripples travelled from the tip to the base of the free-floating depositor moments before the one wrapped in tentacles shot a thick stream of white, cloudy fluid into the water.

Drift reared back wide-eyed with surprise as Wing sagged into Ratchet’s hold and purred with dreamy contentment. He watched the milky fluid of Wing’s orgasm disperse into the current flowing around the rocky outcropping, feeling his own depositors throb.

He flat-out envied the other mer’s happy post-coital purring.

Drift had never been this horny in his entire life.

“You wanna see what Ratchet has?” Wing asked, snuggling deeper into the red and white tentacles that were lapping over him. “It’s a lot less complicated so it’s probably a lot closer to what you’re used to.”

Drift frowned, tilting his head to the side as he studied the mass of shifting red and white that wouldn’t hold still long enough for him to get a good look at… well, anything really.

“What the fuck do you mean, Wing?” Drift asked frustratedly, curiosity getting the better of him as he came within arms’ reach of Wing and Ratchet. “In case you somehow _forgot_ while he was blowing your mind, both of you aren’t _anything_ like what I’m used to.”

Ratchet grinned and shifted his grip on Wing in a way that kept the mer close but also allowed Drift to get a better look at the point where tentacles met and merged into the octomer’s body. Wing trilled, tucking one arm behind Ratchet’s back and using the other to stroke the tentacle wrapped around his own waist.

“What was that human-fry song you taught me?” Wing asked, answering himself before Drift could speak. “Oh yeah, I remember! _One of these things is not like the others; one of these just isn’t the same_.”

While he sang, the mer exaggerated his petting of the tentacle. Ratchet looked torn between the urge to laugh and the desire to throttle Wing.

Understanding hit Drift like a ton of bricks.

“No way. No _fucking_ way.” He glanced between Ratchet’s face and tentacles, half-hoping he wasn’t wrong. “ _Your tentacles are all dicks?!_ ”

Wing and Ratchet shared a long, sober look before dissolving into howls of laughter.

Drift lunged forward angrily and smacked them both lightly on the sides of their heads. A tentacle curled lightly around one wrist and Drift found he suddenly didn’t care what it was or where Ratchet decided to put it. He raised the trapped wrist to eye level, poking at the red suckers carefully with his free hand.

“Alright, yeah it _was_ kinda funny. But what the hell am I _supposed_ to think?” Drift asked as Ratchet calmed and Wing struggled to get himself under control. “Everything is so weird down here that for all I know you _do_ have eight dicks.”

“What this giggling idiot meant is that while I only have _one_ dick, it _does_ look a lot like a tentacle” Ratchet said as Wing continued to giggle, “It’s a short, modified limb that extends from my body cavity when I become aroused.”

“He can control it like his tentacles though; and it leaves a _lovely_ little present behind.” Wing said lecherously, purring and nuzzling deeper into Ratchet’s hold before gasping “Eight dicks, _eight!_ ” and dissolving into giggles again.

“Is he always like this after he cums?” Drift asked dubiously, eyeballing the hysterical mer.

“Unfortunately.” Ratchet said with a long-suffering sigh.

“Crap.” Drift slowly brought his tentacle-wrapped wrist to his lips and brushed it with a gentle kiss. “You should probably do the next part of your demo with me then so we don’t end up murdering him to get some fucking sanity around here.”

When his words made it through the satisfied fog in Wing’s head the mer wriggled so enthusiastically he almost shot right out of Ratchet’s loose grip and brained himself on the rocks.

“ _We wo-on we wo-on!_ ” Wing sang, drawing death glares from both Drift and Ratchet and earning a tighter hold from the octomer.

“ _Ratchet_ won, I’m not so sure about your crazy ass all high from tentacle handjobs.” Drift said scathingly, before shooting a worried look at Ratchet. “He’s not, is he? High I mean. I know you’ve got some kind of venom but you didn’t like, _poison_ him or something while you were jerking him off?”

Ratchet shook his head, squeezing Drift’s wrist reassuringly.

“The venom sacs are beside my salivary glands. It’s why octomer don’t do love-bites.” Ratchet looked relieved when Drift relaxed again, letting himself be drawn closer. “One more thing you need to know before we continue is that I don’t shoot everywhere the way mer do. It’s all in a sort of, well, a squishy packet that gets left in your brooding chamber.”

Ratchet let Drift digest that information for a minute. He could feel the once-human’s elevated body temperature but determinedly kept his eyes away from Drift swollen genital slit. He wasn’t sure he’d be able to keep his tentacles away if he let himself look.

Wing had no such compunctions, blatantly ogling Drift as the mer thought and stroked the tentacle wrapped around his wrist, chasing the shifting colours with a gentle clawtip.

“Sounds a lot tidier than having a bunch of gunk leaking out of me.” Drift eventually admitted, moving the last few feet to press himself against Ratchet’s side in a much less innocent way that he had earlier.

Ratchet made a choking noise and Wing crowed with laughter, twisting around to drop a kiss on Drift’s nose before pressing their foreheads together.

“You don’t _leak_ , silly.” Wing said, smiling merrily into Drift’s snarling face.

“Enough of that, you.” Ratchet said, hauling Wing back before Drift took a swipe at him. “He’s got to be hurting by now. Have some consideration!”

Wing looked contrite, mouthing ‘Sorry’ in Drift’s human language instead of mer so he would be understood.

“So; how do you want me, Drift?” Ratchet rumbled, trying to restrain his urge to envelop the younger mer with as many limbs as he could. “Do you want me to fill you? To pacify your cloaca and satisfy that empty ache deep within? Or would you rather fill _me?_ Relieve your throbbing depositors in me. Fuck me into the ocean floor until we’re both so sated we can barely move?”

Drift shivered as Ratchet spoke, mental images combining with the low infrasound tones to turn every fibre of his new body to jelly. Both options sounded _amazing_. Gentle tentacles curled around his torso, staying away from his pelvic fins and the puffy area between them until he made his decision.

“That’s not fair, Ratch!” Wing said, sounding significantly less giggly now that his afterglow was receding. “ _How_ is he supposed to choose when you word it like that?”

“That’s the _point_ , small fry.” Ratchet retorted. “Drift has to choose what _he_ wants, not what he thinks I want.”

Wing made an apologetic motion with his fins and burrowed into Ratchet, reaching a hand across the octomer’s red and white torso to tangle his fingers with Drift’s.

Taking Ratchet’s words to heart, Drift thought about it carefully. The combination of familiar desire with this new empty ache was driving him up the wall. No matter how weird this was he needed relief and needed it NOW.

That decided him.

“I think I want the first one.” Drift said, pressing his head into Ratchet’s chest and giving Wing’s hand a little squeeze. “Then I’m going to fuck Wing so hard he’ll be laughing for a _week_.”

As soon as Drift made his choice clear Ratchet relaxed the iron control of his limbs. The octomer allowed some to wind more securely around Drift’s torso while two slid down the long, lean body until they encountered his pelvic fins. From there they dipped inward, gently massaging the hot, swollen flesh of his genital slit.

Drift tensed and hissed through his teeth. The inadvertently extended breeding cycle had him so hypersensitive that Ratchet’s light touch was excruciatingly tickly. When the octomer used a little more pressure the tickling faded beneath an onslaught of pleasure.

“Where do you want me for this, Drift?” Wing asked, rubbing his thumb over Drift’s knuckles to get his attention.

Blue eyes opened and Drift tightened his grip on Wing.

“Here. Stay. Please? Want you both.” Drift’s voice was rough, the fog of lust clearing from his mind as he thought about Wing leaving. “Don’t really know what I’m doing. Show me?”

“ _Gladly_.” Wing breathed, beaming across the writhing red and white.

Ratchet showed his own enthusiastic agreement with the idea by manipulating the two mer in his hold until all three of them were within easy reach of each other. He had one arm around Wing and the other supporting Drift while he continued to soothe the recently-made mer’s tender genital slit. Wing settled himself happily with his head against Ratchet’s shoulder; free hand wandering to where Drift’s depositors were standing stiffly out from his body.

“I can’t wait to feel you inside me.” Wing said, pressing the palm of his hand firmly into the warm flesh at the top of Drift’s genital slit. “You’re going to feel amazing, going so _deep_ inside and then swelling to lock me to you while Ratchet holds us, keeps us safe while you fill me.”

Drift moaned, thrashing as Wing’s words brought the heat of the breeding cycle roaring back to full strength. Ratchet rumbled a soothing purr and held Drift a little closer as he let his hectocotylus emerge from the protective camouflage of his main body of tentacles. Its unchanging colouration gave it away and Drift reached with his free hand, stopping just short of touching.

“Please, explore me.” Ratchet urged, sliding the tip of a tentacle over Drift’s cloaca just as curious fingers made contact with his hectocotylus.

It was all the permission Drift needed to run his hands in curious strokes all over the smooth, firm tube that was apparently going inside him. It was proportioned to Ratchet’s frame, which was to say bigger than expected once you ignored the shifting colours and convinced him to hold still.

“That’s seriously going to fit?” Drift asked doubtfully.

Wing nodded vigorously, stroking his hand down Drift’s side in long soothing motions.

“Shall I show you?” The octomer’s voice was strained; the infrasound underlying his words sending pure heat through both mer.

“Alright.” Drift forced out, the sound more than half clicks as he arched to give Ratchet better access to his genital slit.

Wing hummed at Drift’s enthusiastic physical response, enjoying the vibration of Ratchet’s groan as the two tentacles that had been soothing Drift slid behind his tail, raising and moving the mer’s lower body so the twitching cloaca was within easy reach of his hectocotylus.

Drift felt Wing’s hand join his own on Ratchet and together they guided the octomer so the tip of his hectocotylus was nudging Drift’s heat-swollen opening.

“How does th- oh. _Oh_.” Drift’s question was answered before he got halfway through, his words becoming lost in a long moan of pleasure.

Ratchet’s reproductive appendage gave a twitch against Drift’s cloaca and the vent opened, allowing Ratchet to slide inside with next to no resistance. The passage beyond was soaked with a slick discharge that eased the way for the octomer as he thrust deep.

It was _perfect_.

The feeling was everything Drift had been craving without knowing for the last week as his changed body assaulted him with steadily increasing arousal and an uncomfortable achy feeling he’d only really been able to identify when Ratchet gave him his options.

The octomer’s hectocotylus was warm and firm, spreading him open in a way that had Drift sobbing as that annoyingly indefinable craving was _finally_ satisfied. Wing tightened his grip on Drift’s hand, rubbing the other one in soothing motions over the once-human’s abdomen where the belly of another finned mer would press. Between them Ratchet rumbled a constant soothing sound as Drift’s hips began to twitch in the action of mating.

There was a moment of confusion as the old human habit of thrusting forwards fought with the instincts of his new body.

Drift quickly figured out that the side-to-side flicks that were much like swimming shifted Ratchet’s shaft inside him in the more satisfying way and sank quickly into the rhythm. His moan turned into a series of throaty grunts in time with the motion of his hips as pleasure slowly built within him.

It didn’t take long for Ratchet to work his way to the end of Drift’s internal passage, hectocotylus easily finding the opening of the mer’s brooding chamber and moulding itself to the space. He rumbled as contact was established, head jerking back and tentacles twisting so tightly around both mer that he could tell he was leaving sucker marks.

“Yessss.” Wing hissed, wriggling in the tight grip.

“ _Fuck_ yes.” Drift spat before he arched, gasping and trying to force more of Ratchet inside himself.

The heat and shifting pressure of the young mer around him was almost more than Ratchet could stand. He was already unbearably worked up from the shock of seeing Drift’s inflamed genital slit and then feeling Wing come undone so nicely in his grasp.

He wasn’t sure if it was a good thing or not that Drift’s first experience with his cloaca was likely to be so short.

Remembering Drift’s reactions to his light toucher earlier, Ratchet realised it was probably a good thing that he wasn’t going to last much longer. Drift was probably feeling bad enough from the untended breeding cycle; Ratchet didn’t want to add to his discomfort by accidentally fucking him raw!

“I’m close.” Ratchet warned his voice hoarse and strained.

“ _Please_.” Drift moaned. “It still feels empty. I can’t… can’t…”

He bucked again to demonstrate his point, compressing the flesh already stuffed inside him and forcing another inch or two in through his cloaca. Drift’s mouth hung open and his eyes were closed, gills flaring in desperate gasps as he sought blindly to ease the ache in his breeding chamber.

“It’s alright kid, I’ve got you.” Ratchet soothed, meeting Wing’s eyes and nodding.

Wing resettled his grip on Drift’s hand and pressed his other one firmly against the other mer’s belly as Ratchet cried out and his entire body jerked in orgasm. Tentacles and arms clamped tightly around his partners, the tip of his hectocotylus eased the opening of Drift’s reproductive chamber just wide enough to expel a gelatinous sperm packet though it to fill the receptive space beyond.

The alien sound and feeling of Ratchet’s release didn’t detract from the wonderful relief that burst through Drift as a sudden pressure inside silenced the gnawing emptiness that had been plaguing him. He pressed into Wing’s hand, arching against Ratchet’s hold as he announced his own orgasm with a shouted obscenity that made Wing smile fondly and shake his head as he continued to imitate the press of another mer where Drift’s body needed it.

Wing maintained the pressure until Drift relaxed, sagging into the limbs surrounding him.

Ratchet took a bit longer to pull himself from the full-body lockup of his own orgasm.

When he did the octomer purred with satisfaction, rubbing apologetic hands and tentacles over the deepest marks he’d left on his lovers. His hectocotylus began to retract, leaving Drift’s body in a decadent slide that sent tingles through them both. Drift moaned low in his throat, closing his eyes and cuddling into the large octomer’s side with a dopey grin plastered across his face.

 “Ratchet? I think you broke him. He looks _happy_.” Wing teased, tracing the curve of Drift’s smile with a gentle finger.

The octomer growled and Drift’s eyes snapped open. He used his grip on Wing’s hand to yank the yellow-eyed mer close, trapping him against a smirking Ratchet. The octomer helpfully shifted his grip so Wing couldn’t escape.

Two helpful tentacles grasped Wing’s wrists so Drift could let go and put his hands to better use.

“Thanks, Ratch.” Drift said absently before his face lost all traces of post-coital contentment and he glared at Wing.

“You wanna see _happy?_ ” He growled, reaching low and sliding his hands over Wing’s pelvic fins.

Wing tried to twist away from the bold touch, looking extremely pleased with himself.

“Didn’t you say something about making me come so hard I’ll be laughing for a week?” The captive mer retorted, using the little freedom of movement Ratchet allowed him to undulate his body against Drift. “I _definitely_ want to see you try to make good on that.”

Drift cocked his head at the challenging grin plastered across Wing’s face and looked past him to the content and rather smug-looking octomer that held them both.

Now that his passage and brooding chamber had stopped nagging at him Drift could feel his depositors throbbing with a more familiar feeling.

They felt hard and full in the kind of way that demanded something be let out instead of the oddly comfortable fullness that came from Ratchet’s release that was still inside him. He slid his hands down Wing’s torso and between his pelvic fins, searching carefully for the other mer’s cloaca.

“Does it matter which one I use?” Drift asked, leaning forward to nibble gently at Wing’s crest while maintaining eye contact with Ratchet.

Wing’s squeak turned into a moan, pelvic fins smacking against Drift’s extended depositors as he flailed in Ratchet’s hold, trying to move into and away from the sensations Drift was causing with hands and mouth.

Ratchet shook his head, twisting to help position the two mer so Drift could enter Wing with a minimum of fuss.

“Doesn’t matter at all.” Ratchet lowered his voice to the low growl complete with infrasonics that set both mer alight. “Give it to him, kid.”

He didn’t need to be told twice.

With a motion that was easier than anything that had happened since meeting these mer Drift thrust his hips forward. Ratchet provided unobtrusive guidance, using the barest of touches to adjust Drift so that one depositor slipped inside Wing’s hot and welcoming cloaca while the other positioned itself in the crease of a pelvic fin, able to access empty water without being crushed between their bodies.

When he felt Wing’s cloaca open to greet him Drift closed his eyes and buried his face in Wing’s shoulder.

The sensation was familiar and alien all at once.The hot, pulsing squeeze of a passage around his shaft was something he remembered from his old body, but the way the other depositor remained outside was slamming him with alternating waves of right/wrong/right.

“Oh Drift, _Drift_ I was right. You feel so good.” Wing moaned shamelessly, his hips twitching in the same side-to-side motion Drift had been confused by earlier.

Drift was caught off-guard again by the swaying sideways movement where he had been expecting a more human motion. Ratchet came to the rescue, moving him in tandem with Wing to keep either of the finned mer from being damaged.

It didn’t take long for Drift to catch on and let the breeding instincts of his new body take over.

The rippling motions of Wing’s muscles as he moved transmitted through the soft walls of his passage in the most intoxicating way and Drift let himself go, flowing with the movement. He kept his face buried in Wing’s shoulder and concentrated fiercely on the noises coming from the yellow-eyed mer and how intensely _good_ this felt to ward off the strangeness that lingered, threatening to overwhelm him.

Wing was whimpering raggedly, clicking and gasping half-words in Mer that Drift didn’t have a hope of understanding. Ratchet embraced them both with a grip that was firm and gentle, his aroused rumbling and low words of encouragement layering beneath the beneath the higher sounds of Wing’s pleasure.

Drift lost track of time as he floated in a haze of breeding lust, wrapped in Ratchet’s multi-limbed embrace with his depositor buried so deep within Wing they were pressed belly to belly and Ratchet’s infrasonic purr vibrated through all three of them as if they were one giant, complicated sea creature that existed only for this.

Bliss built within Drift, fuelled by the unfamiliar feeling of the depositor inside Wing slowly expanding, spreading the walls of the mer’s passage open apart in a way that Wing clearly and vocally enjoyed. Something throbbed deep in his belly, pressure building in his depositors until pleasure came dangerously close to pain.

A shudder started at the nape of Drift’s neck and ran the length of his spine, sending all of his fins wide. He felt the first pulse of his milt explode into Wing’s passage a split second before the sheer pleasure of orgasm overwhelmed him and he clung to the support of his mates, moaning helplessly into Wing’s shoulder.

The hot flood from Drift’s depositor triggered Wing’s own orgasm, which was _much_ louder than the previous one.

“Oh yes, _yes Drift YES!_ ” Wing wailed, words devolving into a high trill that somehow sounded more erotic than any porn soundtrack Drift had ever heard.

Drift could feel the other mer’s flesh convulsing around his swollen depositor which was acting as a plug to keep the fluid inside. The pressure in Wing’s passage dropped slowly as his body drew the thick fluid away somewhere deep inside.

Eventually the spasms slowed and stopped. When they did Wing’s trilling lapsed into little irregular chirps and he wrapped his arms around Drift. Their bodies remained locked together and Ratchet brought them up to lean against his chest, arms supporting their shoulders while his tentacles moving gently over the finned mer as they basked in the after-effects of mating.

“There’s that happy face again.” Wing observed, giggling softly and running a finger down Drift’s nose.

Drift snapped lazily at Wing’s hand, declining to chase it in favour of resting his head back against Ratchet’s chest.

“Shut up and cuddle.”

Still laughing, Wing obeyed.


End file.
